The present invention relates to a holder for electro-pneumatic components for automotive vehicles. Electro-pneumatic components are, for example, electro-pneumatic pressure transformers or electromagnetic reversing valves.
Electro-pneumatic pressure transformers are described in EP 0 105 808 and DE 41 10 003, for example. Such pressure transformers may have three pneumatic ports, one port being connected to a vacuum generator, another port being connected to ambient or atmospheric pressure, and the third port being connected to a load such as an exhaust gas recycling valve. Using a double seat valve, a pressure in the range between the ambient pressure and the vacuum can be set at the port connectable with the load. Depending on the position of the valve, the pressure supplied to the load can be set within this range. For actuation, the valve is connected to a solenoid plunger system so that, by applying electric signals, the valve can be switched or the position of the valve piston can be varied.
An electromagnetic reversing valve is described in DE 44 19 875, for example. Such valves typically comprise three pneumatic or fluidic ports, where two inlet channels are merged into one outlet channel and the outlet channel may selectively be connected with one of both channels. To switch the valve, an armature is provided that is surrounded by a magnetic coil. The armature which may be displaced by switching the magnetic coil serves to close one of the two inlet channels, respectively. Similarly, the armature could be located in an intermediate position so that a predetermined mixing ratio of the two fluids flowing through the supply channels.
The above-described electro-pneumatic components that have at least one and usually several pneumatic or fluidic ports are employed in automotive vehicles to control loads such as exhaust gas recycling valves or reversing valves. Since these electro-pneumatic components are sensitive to vibrations, they are individually mounted in the vehicles with screws and are fastened, for example, with vibration dampers at the body or another part of the vehicle. After the components have been mounted in the vehicle with vibration damping, these are wired individually and connected to corresponding hoses. The mounting of such electro-pneumatic components is thus extremely troublesome and costly.
It is the object of the present invention to simplify the mounting of electro-pneumatic components.
The invention provides a common holder for a plurality of electro-pneumatic components for automotive vehicles. The holder comprises a base plate with fastening elements for fastening the holder to the vehicle. By these fastening elements, the base plate can be mounted in the vehicle, for example due to interposed vibration dampers. Thus, only the base plate has to be fastened, not each individual electro-pneumatic component. This already allows to save time and costs during assembly.
According to the invention, the base plate comprises holding elements for releasably retaining the electro-pneumatic components. The holding elements may be spring brackets, catches, and the like, for example. Preferably, the holding elements are designed such that the electro-pneumatic components may be connected with the base plate in a simple manner, for example by being pressed into a catch or the like. This is particularly advantageous in that connecting the electro-pneumatic components with the base plate may be effected as a pre-assembly step and that the pre-assembled base plate can then be mounted in the vehicle, e.g., at the assembly line. Thus, a further reduction of the costs is possible. Further, the components are easy to replace.
Since electro-pneumatic components are sensitive to vibrations and impacts, the present holder comprises a fixing element. The fixing element presses the individual electro-pneumatic components against an abutment, whereby they are fixed in the holder in a manner resistant to vibrations. In particular, the provision of the fixing element allows to compensate for manufacturing tolerances. Thus, the preferably elastic fixing element ensures that the electro-pneumatic components are fixed in the holder in a manner resistant to vibrations. Preferably, the fixing element is constructed such that even at the worst possible addition of tolerances no rattling or vibrating of the electro-pneumatic components in the holder can occur. This is achievable in particular with an elastic fixing element that is compressed when mounting the electro-pneumatic components and presses the component against an abutment.
Preferably, the holding elements are designed as catch elements, each holding element comprising a pair of elastic holding arms. The two preferably opposite holding arms are elastically connected to the base plate of the holder. Preferably, the holding arms comprise lugs that partly embrace the electro-pneumatic component. Thus, the component may be mounted by simply pressing it in between the two holding arms.
According to a particularly preferred design of the lugs they simultaneously serve as abutments for the fixing element. Thus, the lugs serve the double function of locking or click-in noses, on the one hand, and of abutments, on the other hand. In this embodiment, the fixing element is a small elastic plate, such as a rubber disc, for example, arranged on the base plate opposite the abutments. However, it is also possible to construct the fixing element as a resilient rib connected with the base plate, preferably by injection. Such an elastically resilient rib also presses the electro-pneumatic components against the abutment.
A particularly preferred embodiment of the present holder comprises a lid to be connected to the base plate so that the electro-pneumatic components are arranged within a housing formed by the base plate and the lid. Preferably, a sealing element is provided between the lid and the base plate. To form the housing, the base plate is either integrally connected with side walls so that a sort of box is obtained on which the lid may be placed and connected therewith by means of a snap connection or the like, or the side walls are fixedly connected to the lid so that the lid is set on a substantially planar base plate.
It is particularly preferred, to design the lid and/or the base plate such that contact elements are provided in the lid and/or the base plate which may be connected with electric terminals of the individual electro-pneumatic components. Here, the contact elements are connected with electric lines encapsulated in the lid or the base plate, for example. Specifically, the contact elements are arranged such that upon insertion of the electro-pneumatic components into the holding elements or upon closing the holder with the lid, an electric contact is established automatically between the contact elements and the terminals of the electro-pneumatic components.
Further, it is particularly preferred that pneumatic ports of the individual electro-pneumatic components are connected by pneumatic lines or hoses. In particular with a holder holding a plurality of electro-pneumatic components where one port is connected with the same pressure generator, it is possible to combine these ports. With electro-pneumatic pressure transformers, these are usually the ports connected with a vacuum generator, such as the air intake system, and those ports that are connected to ambient or atmospheric pressure.
It is particularly preferred, to also provide these pneumatic lines in the lid or in the base plate, the ports to those pneumatic lines being arranged such that already upon mounting the individual electro-pneumatic components or upon closing the housing wit the lid, an automatic connection of the connectors and the pneumatic lines is achieved.